There is technology in which an image display device such as a projector device or the like is used to project an image onto a projection surface such as a screen, a wall, a floor, etc. The projection surface has various colors. Therefore, when the input image is projected onto the projection surface as-is, the color of the projected image may be different from the color of the input image. There is technology that corrects the input image to reduce such a difference. In such an image processor, it is desirable to project an image having higher quality.